Glossary Of Terms

Glossary Of Terms
Glossary Of Terms

Video: Glossary Of Terms

Отличия серверных жестких дисков от десктопных
Video: Watch Terminology: Basic Terms You NEED to Know! 2023, February


Ablation - or rapprochement, is used when other methods of vaccination fail. On the stock on the opposite side of the trunk from the eye, a small section of the bark is cut off. Likewise, a strip of bark is removed from the scion. Places with cut out bark are connected, tied up and covered with garden varnish. In this case, the scion is separated from the mother plant only after it grows together with the stock.

Abscisic acid is a plant hormone. By its chemical nature, it is isoprenoid. It induces and increases the dormancy period, accelerates the formation of a separating layer when leaves fall, inhibits the growth of stems and coleoptiles. Accumulates in seeds and buds in autumn. The level of abscisic acid in tissues depends on the ratio of its synthesis and degradation (oxidation) or binding (glycosidation). The biosynthesis of abscisic acid and growth hormones - gibberellins - occurs from a common metabolic precursor - mevalonic acid. It is believed that there is a system for switching the pathways for converting mevalonic acid to abscisic acid or gibberellins, regulated by an excess of one of these products.

Acaricides - from acarus - mite, - preparations destroying herbivorous mites. Not to be confused with insecticides! Ticks belong to the class of arachnids, the rest of the majority of flower pests (thrips, caterpillars, scale insects) belong to the class of insects, therefore insecticides do not work on the tick. Moreover, very often long-term use of the same drug causes addiction of the pest, as a result, some of the individuals survive, reproduce, and do not lend themselves to the effects of the previously used agent. Therefore, it is recommended to alternate spraying with various preparations when fighting ticks.

Axilla - from lat. axilla - armpit, is the sinus between the papillae in some genera of cacti. It is from the axilla that flowers, new shoots, spines (and modified spines - hairs) develop. Axilla is the point of growth.

actinomorphic flower
actinomorphic flower

Актиноморфный цветок - от греч. aktis - луч и morphe – форма, – правильный цветок, имеет более двух плоскостей симметрии (симметрия определяется по околоцветнику, чаще всего - по венчику). Характерен для многих семейств двудольных и однодольных. Актиноморфные цветки могут быть раздельнолепестными (у гвоздичных, розовых, зонтичных) или спайно­лепестными (у паслёновых, колокольчиковых). Часто опыляются насекомыми, поэтому иногда у актиноморфных цветков, как и у зигоморфных, вырабатываются различные приспособления для опыления специализированными опылителями (чешуйки в зеве, очень длинная трубка венчика и т.п.).

Androeus is a collection of stamens on a flower (see Flower). The shape of the androecium can be different in different families and genera of plants. So in buttercups and cactus, adnrocea is a spiral. In Rosaceae, the stamens are arranged in a circle. In some plant families, androecium is represented by stamens accreted at the base, i.e. is a bunch of stamens. And for example, the seed pea has only 10 stamens, while 9 of them are fused at the base, and one is separate, see stamens.

Apex - from the Latin apex, genus. n. apicis - top. This is the apex of the shoot and root, consisting of the primary meristem, which ensures the formation of all parts and primary tissues of the shoot. On the apex of the shoot, protrusions are formed - tubercles or ridges (leaf buds), the so-called leaf primordia. The root apex is always smooth.

At the apex of the shoot, only the cone remains smooth. In terms of shape and size, the apexes can be different not only in different species, but also in one plant or an individual shoot at different periods of its morphogenesis. Apex classification has not been developed. Usually they are divided into 3 types: with one initial cell of the apical meristem (fern-like), with several initials in one layer (gymnosperms), with several initials in two or more layers (most flowering). Often, the terms Shoot Apex and Root Apex are used synonymously with the term “apical meristem”. The apex is often referred to as the taper.

Apocarp - complete loss of the ability to produce fruit.

Apocarpius is a fruit formed by free or partially accrete carpels.

Area - from lat. area - area, space, - part of the earth's surface (territory or water area), within which a given taxon (species, genus, family, etc.) is distributed and goes through a full cycle of its development. The range is as much an integral part of the characterization of a taxon as morphology and its ecological features. The space in which the formation of the species takes place is called the primary area. The formed area can then expand as a result of dispersal or decrease due to the extinction (or destruction) of the species on parts of the space inhabited by it.

Arillus - from lat. arillus - mantle, seeding, roofing. Usually a fleshy formation that occurs in many plants on a seed or seedling and partially or completely covers the seed. Arillus fabrics, as a rule, contain sugars and oils. Arillus promotes the spread of seeds by animals, for example, ants (celandine), wind, water, sometimes - the opening of the fruit (nutmeg), the separation of the seed from the placenta (broom). False Arillus (arylloid) arises from the integument tissue and does not close the micropyle when it grows. This is either a small outgrowth in the micropyle area (euphorbia, istode, boxwood) - a caruncle, or a glandular outgrowth along the seed suture (celandine), or in the area of ​​the seed stalk. Mature Arillus is often brightly colored (yew, euonymus).

Areola is a modified bud, which is a growth point, characteristic only of representatives of the cactus family. In the same way that ordinary plants have apical and lateral buds, a cactus has an apical areola, the so-called axilla and lateral areoles. Many cacti are capable of stopping the growth of isaxilla at some point and starting to develop shoots from the lateral areoles. This ability is genetically assigned to individual plant species. That is why "babies" so easily form mammillaria, and cerius literally grow in a column. It is from the areolas of the cactus that thorns grow and flowers appear.

Assimilation is the process of the formation of chemicals through the processes of photosynthesis.

Auxins - from the Greek. auxano - increasing, growing, - plant hormones, indole derivatives.Formed in the apical meristems (see apex) and stimulate cell expansion. One of the most widespread auxins is beta-indolyl-3-acetic acid (IAA), or heteroauxin, the biochemical precursor of which is tryptophan. Auxins stimulate the growth of coleoptiles (a hollow cylindrical formation surrounding an unfolded leaf in a monocotyledonous plant seedling), stems, leaves and roots, cause their bends, and also enhance root formation in cuttings. The action of auxins facilitates the stretching of the growing cell under the influence of turgor pressure. Auxins also enhance cell multiplication in callus cultures (see callus) and during the formation of adventitious roots in cuttings. In combination with cytokinins, uxins stimulate cell differentiation and induce the formation of roots in tissue culture.

An acyclic flower is a spiral flower, all elements of which (tepals, stamens, carpels) are arranged in a spiral. The receptacle is usually convex, often conical. Acyclic flowers are characteristic of primitive flowering plants, mainly polycarpous (magnolia, buttercup, etc.). Acyclic flowers are usually actinomorphic, less often zygomorphic (aconite, larkspur). From A. c. hemicyclic and cyclic flowers have developed.

Aerofits - from the Greek. aer - air, - "aerial" plants that receive all the necessary nutrients from the atmosphere. Aerophytes include epiphytes, as well as some mosses that inhabit tree trunks and branches (and even leaves), very few algae that live on tree bark, and some lichens.


Basal leaves
Basal leaves

Basal leaves are leaves growing at the base of the trunk (stem), usually forming a basal rosette. They often differ in size and shape from the leaves that grow on the upright stems of the plant.

Bulba (pseudobulba) is a thickened part of the stem in sympodial orchids. They act as a reservoir of nutrients and water in case of prolonged drought, which is typical for plants leading an epiphytic lifestyle. Bulbs have various shapes, depending on the type of orchid - cylindrical, cone-shaped, club-shaped or spherical. Each bulb has one or two leaves. But since the reserves of nutrients are in the bulbs, the leaves of such orchids are usually thin and narrow, gradually dying off. Monopodial orchids do not have bulbs and their reserves of nutrients and water are deposited in juicy fleshy leaves.


Vaya (from the Greek baion - palm branch) is a large, highly dissected, branch-like fern leaf (sometimes palm leaves).

The growing season or vegetation is the period from sowing to the ripening of a flower (fruit, medicinal, garden, agricultural crop). Quite simply, a period of growth. In our latitude, it lasts from about March to September. At this time, plants grow and consume nutrients, therefore, it is at this time that transplantation and fertilization are carried out.

Vegetative organs are parts of plants that perform the main functions of nutrition and metabolism with the external environment. They are not directly involved in sporulation and sexual reproduction, but they can perform the function of vegetative reproduction. The main vegetative organs are stems, leaves (providing photosynthesis) and roots (providing water supply and mineral nutrition).

Vegetative hybridization is the production of hybrids by grafting, i.e. by artificially combining plants belonging to different species or genera into a physiologically unified organism. Vegetative hybridization is aimed at changing the metabolism and thus the nature of the organism. When influencing the metabolic processes between the scion and the stock, it is possible to control the degree of influence of the stock on the scion, or vice versa, the scion on the stock.

At the same time, of the two parts of the plant obtained by grafting, that will experience a greater influence, which is younger in age.

Young seedlings of hybrid origin are the most variable under the influence of grafting. Michurin developed the so-called mentor method - when a hybrid seedling to be nurtured is grafted with a plant of another variety, the stock is called a mentor - which means "educator." Only plants with established heredity and low variability are used as a mentor. The mentor can be not only the rootstock, but also the scion.

Corolla- from corolla - inner, - usually a brightly colored part of the double perianth, consisting of petals. The corolla can be divisible (brunfelsia) and spine-petaled or spine-petaled (in loach, nightshade). Usually, the corolla is the most noticeable part of the flower, characterized by a variety of shapes, colors and sizes, and is one of the fundamental species and varietal differences, due to its high evolutionary plasticity, i.e. the ability to undergo morphological variability of stamens in the process of evolution of flowering plants, or in the process of modification of sepals. According to famous botanists: E. A. N. Arber and J. Parky (1907), B. M. Kozo-Polyansky (1922), A. Eames (1961) and J. L. Stebbins (1974), there are two ways of development petals in flowers: "andropetals" (petals from stamens) and "bracteopetals" (petals from bracts).The brightest representatives of the andropetal group are the family of the nymphaeans, begonias, and the bracteopetals group, the Badian and Schizandra families.

A species is a set of individuals possessing common morphophysiological characteristics, capable of interbreeding with each other in natural conditions, and collectively occupying a common continuous or partially ruptured area.

Foliar dressing is a fertilization method in which plants receive nutrients through the leaves. At the same time, a solution of mineral (or complex) fertilizers is diluted, but, as a rule, in a concentration that is two times lower than when applied under the root with water for irrigation and sprayed over the leaf. It should be noted that foliar feeding is best done not in sunlight (some elements decompose under the influence of light, and besides, the plant can get burns).

Brood buds (in flowering plants and ferns) are specialized buds that fall off a plant and give rise to new plants. Brood buds are formed in the axils of leaves, (lilies), on the leaves along their edge (bryophyllum) and veins (asplenium viviparous) or on the whip-like tops of leaves (wandering fern Satptosorus rhizophyllus).


Hemicyclic flower - from the Greek. hemi - semi - and kyidos - circle, - a flower, in which some parts are arranged in a spiral, others - in circles. Most often, the stamens and carpels are located in a spiral, and the perianth is in a circle (some of the Annon family). Sometimes the calyx and carpels are arranged in a spiral, and the corolla and stamens are located in a circle (rose hips). The hemicyclic flower occupies an intermediate position between acyclic and cyclic flowers and is considered primitive.

Heterosis - from the Greek. heteroicsis - change, termination, or "hybrid power" - the superiority of hybrids in a number of traits and properties over the parental forms. As a rule, heterosis is characteristic of first-generation hybrids obtained by crossing unrelated forms: various varieties and even species. In subsequent generations (crossing hybrids among themselves), its effect is weakened and disappears.

Heterostyly - from hetero … and … style, or variegated columnarity - the presence of two or three forms of flowers in plants of the same species, differing in the length of the columns and the location of the stamens. There are even trimorphic forms of plants - with short-, medium- and long-columnar flowers, for example, in willow loot. Heterostyly is the adaptation of plants with bisexual flowers to cross-pollination. Known in representatives of 24 families of flowering plants.

Hypocotyl - from hypo … and Greek. kotylе - depression, bowl, - hypocotyledonous knee, section of the stem of the seedling plant below the cotyledonous node. The hypocotyl passes downward into the root and often has an anatomical structure with features of both the stem and the root. In some plants, the length of the hypocotyl is so short that it remains entirely in the soil, and the cotyledons are not brought to the surface (bast, peas). In others, the tissues of the hypocotyl grow so much that they rise high above the ground, taking bizarre forms (opurcuricaria, ficus microcarp) (see caudex).

Gibberellins are plant hormones from the group of diterpenoid acids. HA 1, HA 2, HA 3 are designated (in the sequence of isolation and establishment of the structure). Having the same molecular skeleton, gibberellins differ from each other in the type, number, and arrangement of functional groups. At low concentrations, gibberellins are widespread among higher plants as endogenous growth regulators. At higher concentrations, gibberellins are produced by the fungi Fusarium moniliforme (causing hypertrophied rice growth), Sphaceloma manihoticola, and possibly other microorganisms. In total, about 40 gibberellins have been identified in plants.

In plants, gibberellins are synthesized in rapidly growing organs - forming seeds, apical stem buds, and less often in roots. During ontogeny, the assortment and content of gibberellins change: during seed germination or flowering, physiologically inactive gibberellins - precursors or related forms of the most active gibberellins - are converted into the latter (for example, in GA 3), and when fruits ripen and pass to rest, active gibberellins form inactive forms (glucosides, glucose esters, as well as catabolic products). The most characteristic physiological effect of gibberellins is the acceleration of organ growth (mostly of the stem, to a lesser extent of the root) due to both cell division and elongation. In addition, gibberellins interrupt the dormant period in seeds, tubers and bulbs, induce flowering of long-day plants on a short day, stimulate pollen germination, cause fruit parthenocarp, and eliminate physiological and genetic dwarfism.

Gibberellins are the only known phytohormones for which a direct effect on enzyme biosynthesis has been proven. For example, in germinating seeds of cereals, gibberellins formed in the embryo pass into the endosperm, where they induce the formation of RNA, which is responsible for the biosynthesis of alpha-amylase and other hydrolytic enzymes. This effect ensures the mobilization of seed storage substances.

Hybrid - from lat. hibrida, hybrida - a cross, an organism (cell), obtained as a result of combining the genetic material of genotypically different organisms (cells), i.e. hybridization. In natural populations of cross-pollinated plants, almost every individual is heterozygous for many genes, i.e., it is a hybrid, which is necessary to maintain a certain level of genotypic variability in the population. Distant hybrids (of different taxa - species, genera, families) are quite rare in nature and, as a rule, are sterile. This suggests that natural selection inhibits both their formation and their survival. However, the appearance of some plant species was associated with the formation of distant hybrids.

Hybridization is the process of forming or obtaining hybrids (or obtaining different varieties, varieties, species and genera), which is based on the unification of the genetic material of different cells in one cell. It can be carried out within the same species (intraspecific hybridization - hybrids are characterized by heterozygosity for many or the analyzed gene) and between different systematic groups (distant hybridization, in which different genomes are combined).

  • Sexual and vegetative hybridization of plants have a common basis, which is the exchange of substances between the connecting components, their mutual assimilation activity (see assimilation).
  • During sexual hybridization in the process of fertilization, both uniting sex cells, both maternal and paternal, assimilate each other. Ultimately, instead of two cells, a new hybrid cell is obtained, which gives rise to a new organism that combines the hereditary characteristics of the paternal and maternal forms.
  • During vegetative hybridization, properties and traits are also transmitted to the offspring, i.e. vegetative hybrids do not differ from hybrids obtained sexually by crossing.

    Hybridization causes wide variation in plants, they have a shattered heredity. This is especially true for those plants that are constantly in the process of breeding new varieties and species (Saintpaulia, roses, etc.).

  • Hybrids often develop completely new properties that the original forms did not yet have. The art of hybridization is precisely to consolidate the received traits.

Hygrophytes are plants of humid habitats; unlike xerophytes, they have no adaptations that limit water consumption. The leaf blades are usually thin, large, with an underdeveloped cuticle (they are characterized by high cuticular transpiration). Stems are long, mechanical tissues are almost undeveloped; the root system is weak, so even a slight lack of water causes noticeable wilting in them. For the most part, these are plants of tropical rainforests and swamps.

Gynoecium is a collection of pistils on a flower (see Flower).

Humus is the most fertile surface layer of the earth. It is organic matter produced by decomposition of plants and the processing of decomposition products by earthworms. They are especially rich in humus, garden compost, peat and black soil. Humus is an indicator of soil fertility. Plants cannot assimilate humic substances directly from the soil - the assimilation process is facilitated by microorganisms.

Guttation - from lat. gutta - drop, - release by plant leaves (through water stomata - hydatodes - at the edges and tips of leaves) of droplet liquid under the influence of root pressure, when the flow of water into the plant exceeds transpiration. Often seen early in the morning or in humid conditions in many plants (monstera). The significance of guttation, apparently, is that the plant is freed from excess water and salts.


Dorsoventral - from lat. dorsum - back and venter - belly - a term used in relation to the structure of thallus plants (lichens, fern sprouts, etc.), as well as flat organs of higher plants, for example, leaves, in which the ventral can be distinguished (in the leaves - the upper inner, in thallus - the lower, facing the substrate) and dorsal (in the leaves - the lower outer, in the thallus - the upper) sides.

Breathing is a natural process that plants have throughout their life. If photosynthesis occurs in plant tissues only during the daytime, then respiration is constantly present. Respiration occurs in all organs and tissues - in all living cells of the plant. The respiration process is nothing more than the process of decay of organic substances with the participation of free oxygen and the release of carbon dioxide and water, accompanied by the release of energy. In conditions of sufficient illumination in tissues, the process of photosynthesis prevails - the process of creating and accumulating organic matter.

With the weakening of the intensity of light, photosynthesis weakens and respiration prevails. The loss of organic matter becomes clearly noticeable in conditions of insufficient illumination of plants, especially in winter. The plant begins to "starve", loses leaves, takes on ugly forms (for example, in cacti). Therefore, in winter, plants should be placed as close to the light as possible, or additional artificial lighting should be provided - this increases the processes of photosynthesis and, to some extent, reduces the consumption of organic matter for the respiration processes.

Since respiration is carried out by the root system, the soil should be sufficiently breathable for all plants, without exception. That is why it is impossible to allow the air gaps between soil particles to be filled with water - the lack of oxygen weakens the respiration of the roots and the supply of nutrients from the soil decreases, in addition, beneficial microorganisms that live in the soil and use oxygen die.


zygomorphic flower
zygomorphic flower

Ovary - according to the position on the receptacle, the upper, middle and lower ovaries are distinguished. The ovary is called superior if it sits freely on a convex, flat or concave receptacle above the base of the perianth. The middle ovary up to half grows together with the receptacle, while its upper half remains free.

The lower ovary is formed when the ovary is completely fused with the receptacle below the base of the perianth. The ovary can be one-, two-, three- and multi-celled.

Zygomorphic flower - from the Greek. zygou - pair and morphe - shape - flower, the perianth of which has one plane of symmetry. Usually this plane passes through the middle of the bracts, the peduncle and the axis of the inflorescence, that is, it coincides with the median plane of the flower (orchids); rarely there are flowers in which the plane of symmetry is perpendicular to the median plane. The appearance of a zygomorphic flower is the result of adaptation to pollination by insects, which can enter the flower in a single way.


Insecticides - from lat. insectum - insect and caedo - kill. Chemical preparations for the destruction of harmful insects on indoor and garden plants and crops.

By the type of impact on the pest, insecticides are classified as:

  • Contact insecticides - neutralization upon contact with the body of the pest. This group of insecticides is rather unstable, can be easily washed off with water, and does not penetrate into plant tissues.
  • Intestinal insecticides - enter the pest's body and poison it. Insecticides are also not resistant to external factors - light, wind, rain or spraying.
  • Systemic insecticides - contain chemicals that are absorbed by the plant and spread through the vascular system to all parts of the plant. The principle of action is the same as that of intestinal insecticides - poisoning of a pest that gnaws or sucks a plant.

Of all the insecticides, systemic ones are by far the best. First of all, for ease of use - I poured a solution on the ground, and that's it, no spraying in a respirator. Example: Aktara and Confidor, which are very effective against a variety of pests: aphids, scale insects, thrips, mealybug (but not effective against ticks).

Intestinal and contact insecticides are applied to the plant by spraying or bathing the foliage in a basin, and therefore require safety precautions (work in a ventilated non-residential area, respiratory protection). To destroy soil pests (larvae of mushroom mosquitoes, root bugs, millipedes, slugs, etc.), the soil is watered with a solution.

According to the types of pests that are affected by insecticides, they are classified as:

  • Continuous action insecticides - against a number of pests (karbofos, actellik)
  • Nematocides - drugs against nematodes (worms), this group of drugs is not used at home due to its high toxicity to humans and animals.
  • Acaricides are drugs that affect only ticks (neoron).
  • Insectoacaricides are drugs that kill both ticks and insect pests.


Callus - from lat. callus - thick skin, callus, is a tissue that forms in plants at the site of wounds and promotes their healing. Consists of more or less homogeneous parenchymal cells, the origin of which will be given by the wound meristem. Callus elements are poorly differentiated, however, near its surface, growth is observed due to the activity of meristematic cells. In the callus, adventitious roots and buds can be laid, the outer cells of the callus cork. Callus (callus) also occurs during grafting, ensuring the fusion of the scion with the stock, at the base of the cuttings. It is used to obtain a culture of isolated tissues.

Cambium - from cambium - exchange, change, is a single-row layer of educational tissue cells, due to which the secondary thickening of plant stems and roots is carried out. The bundle cambium separates inwardly from itself the cells that differentiate into elements of the secondary xylem (wood), and outwards - the cells that differentiate into the elements of the secondary phloem (bast). The cells of the so-called interfascicular cambium form parenchymal cells of the rays that separate the conducting bundles. In plants with active secondary thickening, cambium cells are of two types: long, fusiform, and short, collected in longitudinal cords, forming bast-wood rays. Cambium can be tiered, if on longitudinal sections the ends of the fusiform cells are at the same level, and non-tiered, if they are randomly located.

Caudex - from lat. caudex - trunk, stump, - hypocotyl, located between the root and cotyledonous leaves or leaf in monocots (the structure of the hypocotyl bears the signs of both the stem and the root), has the appearance of a thickening (underground or ground), serves as a supply of nutrients and water. Caudex can have various shapes (spherical, bottle-shaped, pillar-shaped, etc.). The integumentary tissues of the caudex (hypocotyl), as a rule, are corky.

Cambium is a layer of cells of educational tissue found in stems and roots between wood and bast. In the leaves, cambium is located in vascular bundles, between phloem and xylem. Cambium gives rise to secondary conductive tissues. Due to the division of cambium cells, the roots and shoots of plants grow in thickness (mainly dicotyledonous flowering and gymnosperms).

Caudiciform - plants with pronounced caudex. It differs from other succulents in the origin of caudex (from hypocoticle), while other succulents may have thickened leaves, roots and stems.

Kerbovka is a technique that allows you to awaken or slow down the growth of the kidney. This is done by cutting out a small area of ​​the bark above the kidney, if you want to activate its growth, or under the kidney, if you want to extinguish its growth. A stripe with a length of 5 mm is enough (for indoor plants, for example, ficuses) to 2 cm (depending on the thickness of the branch for garden plants, for example, apple trees). An incision in the bark is made in the form of a straight strip or crescent, and on thicker trunks it is more effective to cut the bark with a crescent (crescent). Kerbovka is carried out in early spring, before the buds awaken, see "Kerbovka"

Soil acidity - an important indicator of the suitability of the substrate (soil mixture) for growing certain plants - reflects the concentration of hydrogen ions in the environment. Measured in units of pH (must be indicated on quality soils sold in the store). A neutral medium corresponds to pH 7, acidic below 7, alkaline above 7. Lowering pH means an increase in acidity, and an increase in alkalinity. Soil, which contains a lot of lime, is alkaline. Soil with a lack of lime has an acidic reaction. Most indoor plants require slightly acidic soil, but there are exceptions that prefer an acidic substrate, or vice versa, neutral or alkaline - see "About soil and plant transplantation"

Cladonium is a modified, flattened stem in some plants that do not have true leaves or are rapidly losing them; performs the function of photosynthesis (euphorbia, stapelia).

Coleoptile - from the Greek. koleos - sheath, sheath and ptilon - feather - leaf sheath, the first (colorless, green or reddish) leaf of cereals. Unlike real leaves, it does not have a leaf blade and is a closed tube in which leaf primordia (the first of which is a feather) and a growth cone are enclosed. The coleoptile grows, breaks through the soil with a solid (due to high turgor) top, then breaks, and the first green leaf emerges through the break (develops from a feather). In the future, the coleoptile dries up.

Copulation - grafting by cutting. Growth is successful if the scion and rootstock are of the same thickness. The rootstock is associated with the scion, the grafting site is coated with garden varnish.

Root - radix - one of the main vegetative organs of leafy plants, which serves to attach to the substrate, absorb water and nutrients from it. Phylogenetically, the root arose later than the stem, and probably descended from the root-like branches (rhizomoids) of the first plants (rhinophytes) that emerged on land. Such rhizomondas from living plants have survived only in psilots. True roots originally appeared in lycopods and ferns, the most complex structure in seed plants. The root bud is laid in the embryo and then develops into the main root, which branches endogenously (from the pericycle) and gives lateral roots. On other organs (stems, leaves) adventitious roots are endogenously formed.

The root grows only by the meristematic apex, which is protected by a cap, behind the growth zone is a small suction zone, covered with rhizoderma (epiblema) with root hairs. As the root grows in the soil, the suction zone moves and the old root hairs die off.

Through the root, plants absorb water from the soil, ions of mineral salts, which interact with the products of photosynthesis flowing from the leaves, forming amino acids, nucleotides, and other organic compounds. Through the vessels of the xylem, elements in the form of ions or organic molecules, as a result of the action of root pressure and transpiration, move to the leaves and stems. Alkaloids, growth hormones, and other physiologically active compounds are synthesized in the roots, the roots of many plants (the so-called root suckers) form adventitious buds that give aboveground shoots, and in a number of plants they serve as a place for the deposition of reserve nutrients (root crops).

In some tropical trees, adventitious roots, which serve for support and nutrition, branch off from the base of the trunks or branches - boarding, stilted, pillar-like; vines develop root-attachments, epiphytes develop aerial roots, and some epiphytic orchids have flat green roots capable of assimilation; plants living on oxygen-poor soils (taxodium, mangrove, etc.) have respiratory roots - pneumatophores.

Root and root system - a set of roots of one plant, the general shape and character of which are determined by the ratio of growth of the main, lateral and adventitious roots. With the prevailing growth of the main root, a pivotal root system (lupine) is formed, with weak growth or dying off of the main root and the development of a large number of adventitious roots, a fibrous root system (azaleas). The degree of development of the root system depends on the habitat: in the forest zone, on podzolic, poorly aerated soils, the root system is 90% concentrated in the surface layer (10-15 cm). In the zone of semi-deserts and deserts, in some plants it is superficial, using early spring precipitation (ephemera) or condensation, in others it is very deep, penetrating into the ground for several meters.

Rhizome- from rhizome, - underground, more or less durable shoot of perennial herbaceous plants, as well as shrubs, serving for the deposition of reserve substances, vegetative renewal and reproduction. It differs from the root by the presence of scaly leaves, scars from fallen leaves (sometimes their dry remains), buds and adventitious roots, and the absence of a root cap. The rhizome (rhizome) grows annually and forms aerial shoots from the apical or axillary buds. Rhizomes often form branched systems. The old parts of the rhizome are gradually destroyed. Long rhizomes with significant annual increments and well-defined internodes (wheatgrass) serve mainly for vegetative reproduction and dispersal,short rhizomes with small annual growths and close knots (iris) - mainly for storage and vegetative renewal. Rhizomes are formed or directly in the soil (lily of the valley, blueberries) - the so-called. hypogeogenic, or at first they grow as aboveground assimilating shoots, which then gradually sink into the soil (cuff) - i.e., etc. epigeogenic.

Root pressure - in plants, pressure in the conducting vessels of the roots, providing (along with transpiration), the supply of water to the above-ground organs. It arises mainly as a result of an excess of the osmotic pressure in the root vessels (usually 1-3 atm.) Over the osmotic pressure of the soil solution as a result of the active release of mineral and organic substances by the root cells into the vessels. The reverse flow of fluid from the vessels under the action of root pressure is prevented by a layer of endoderm cells with suberized membranes. The result of high root pressure is “crying” of plants (release of moisture droplets) and guttation.

Root offspring - from soboles, is an aerial shoot of a plant that develops from a root accessory bud. Serves for vegetative propagation of mainly dicotyledonous plants (cordilina, aglaonema).

Root cap - from calyptras, is a protective formation of the growing root tip. Multilayer cone-shaped cap made of living parenchymal cells with mucous membranes and mobile starch grains (statoliths) participating in the geotropic reactions of the root. It differentiates in the early stages of root development from calyptrogen (for example, in cereals and other monocots) or from the apical meristem (in many dicots and gymnosperms). In aquatic plants, the root cap is missing or replaced by a root cap or pocket.

Xerophytes are plants in dry habitats that can withstand prolonged drought. All of them have their own adaptations to adapt to extreme conditions (prolonged heat and drought). Xerophytes make up a typical flora of deserts and semi-deserts, they are widespread in the steppes on the sea coast and in sand dunes, where water is difficult for plants to assimilate due to its low temperature (peat bogs) or because of the high salt content. Xerophytes have a number of adaptive features that allow them to exist under conditions of constant or seasonal moisture deficit: slow transpiration, heat tolerance, etc.

For Xerophytes, the following ecological and physiological classification (according to P.A.Genkel) is proposed:

Succulents: fleshy leaves (agave, aloe) or stems (cacti) and superficial root system; heat-resistant (due to the high viscosity of protoplasm and the high content of bound water in the cells), but do not tolerate dehydration. Hemixerophytes: the root system reaches the groundwater; cannot stand prolonged dehydration; drought tolerant due to uninterrupted water supply, intensive transpiration and metabolism; growing in the steppes (for example, sage) are not heat-resistant, growing in deserts (camel thorn) are heat-resistant. Euxerophytes (for example, some types of wormwood): the root system is branched, but shallow (50-60 cm); the plants are pubescent; they tolerate dehydration and overheating well, since their protoplasm has high elasticity and viscosity, and the metabolism is not very intense. Poikiloxerophytes: when dehydrated, they fall into suspended animation;in this state they contain 2-5% water, the protoplasm acquires a gel-like consistency; however, the organization of the cell is not disturbed due to the preservation of the energy value of respiration until almost complete dehydration. Sometimes other groups of Xerophytes are also distinguished.

Xylem- from the Greek. xylon - (felled) tree - water-conducting tissue of vascular plants. Together with the phloem, it forms a conducting system that unites all plant organs. According to the time and place of formation, it is divided into primary (procambium derivative) and secondary (cambium derivative). Secondary xylem (wood) includes tracheal elements (vessels, tracheids - dead hollow cells that carry out distant, or axial, transport of solutions), parenchymal elements (near vascular cells, cells of the radial and traction parenchyma, carrying out the near, or radial, transport of salts, regulation long-distance transport of salts, storage and short-range transport of plastic substances), as well as fibrous tracheids and fibers of libriform - cells that perform supporting, sometimes storage functions.Secondary xylem accumulates throughout the life of the plant and consists of annual growth rings. The ratio between functioning (sap) and non-functioning (heartwood) wood varies from plant to plant and depends on climatic conditions.


Lateral - from lat. lateralis - side, side, - located away from the median plane, lateral.

Liana - from fr. liane and lier - to tie, - climbing or climbing herbaceous or woody plant with an elongated stem, unable to climb up without additional support.

Sheet - from lat. folium, Greek. phjllon, is one of the main organs of higher plants, occupying a lateral position on the stem and performing the functions of photosynthesis, transpiration, and gas exchange. As a rule, the leaf is a flat organ, the shape of which contributes to the creation of the maximum photosynthesizing surface. The adult leaf consists of a plate and a base (sometimes in the form of a tubular sheath, often with paired outgrowths - stipules). Between the plate and the base there is often a narrowed stem-like part - a petiole (if it is not there, the leaf is sessile). Distinguish between simple leaves (with one plate) and complex (with several plates - leaves located pinnately or palmately on a common axis - rachis).

The shape of the leaf is a characteristic feature of the species, however, within an individual and even one shoot, leaves can vary greatly, forming 3 formations: lower leaves (usually in the form of scales with an underdeveloped plate), middle (most developed) and upper (underdeveloped, in the inflorescence area - bracts). Often the leaves are modified into spines, antennae, storing scales, etc., or are reduced.

On both sides, the leaf is covered with an epidermis with a cuticle, often pubescent with various hairs (trichomes). Under the epidermis is the leaf pulp (mesophyll), represented by several layers of green tissue (chlorenchyme), in which the main physiological processes take place - photosynthesis and plant respiration. The leaf blade is penetrated by the so-called. veins that form its "skeleton" and have a characteristic arrangement. Conductive bundles, usually equipped with mechanical sheaths, pass through the veins. Through the petiole and the base of the leaf, the conducting bundles (leaf traces) enter the stem and connect to its conducting system.

The leaf is an organ with limited growth. The petiole is the last to grow, retaining this ability for quite a long time, which provides the ability to turn the plates towards light (the so-called leaf mosaic).

Lithophytes are plants growing on stones, rocks or in their cracks.

The bulb is a modified underground shoot, with a thickened short flat stem (bottom) and overgrown fleshy or filmy leaf bases (scales) that store water and nutrients, and serve as an organ of vegetative reproduction - monopodial (renewal comes from the apical bud, and flowering shoots are formed from axillary buds, for example, in a daffodil), and sympodial (a flowering shoot develops from an apical bud, and renewal occurs from an axillary, for example, a tulip).


terry hippeastrum
terry hippeastrum

The doubleness of the flower is the growth of the corolla or corolla perianth with an increase in the number of petals. The nature of the formation of petals in flowers is known - they are the result of mutation of stamens during the evolution of flowering plants - see corolla. Terry appeared in the process of morphological changes in individual parts of the flower.

Terry can be true - associated with an increase in the number of petals. And false - associated with a change in the shape and size of the corolla of flowers collected in an inflorescence. True doubleness is most often the result of the transformation (mutation) of stamens into petals (begonias, roses, peonies), pistils into petals (litics, clover). In some cases, terry is due to the division of the petals into lobes (fuchsia) or stamens (clove).

In some cases, doubleness occurs as a result of an increase in the number of perianth circles (tulips, lilies).

False doubleness is common in the Asteraceae family - the middle bisexual flowers turn into ligulate, or peripheral ligulate flowers turn into tubular. Terry can be complete - when all the stamens or pistils turn into petals, partial (semi-double flowers) when only part of the stamens or pistils are converted into petals.

Getting terry varieties as a result of selection is sometimes not difficult, sometimes it is not achieved without effort, it all depends on the evolutionary plasticity of the family and species. More precisely, on the ability to keep the stamens and pistils functioning. In a number of plants, for example, fuchsias, they are completely preserved and easily pollinated, in others, for example, petunias, begonias, carnations, stamens or pistils are partially preserved and plants are able to set seeds during artificial insemination. In other cases, the reproductive organs are completely transformed, and seed reproduction becomes impossible.

Mesophytes are plants that live in conditions with more or less sufficient, but not excessive amount of water in the soil; intermediate group between xerophytes and hygrophytes. Mesophytes predominate in the temperate zones; there are many of them in the forests of the tropics and subtropics.

An interspecific hybrid is a hybrid obtained by crossing two species belonging to the same genus.

Meristem- from the Greek. meristos - divisible, - the educational tissue of plants that retains the ability to divide and create new cells for a long time; has a high metabolic activity. Some cells of the meristem are initial, they are delayed at the embryonic phase of development and, dividing, provide a continuous increase in plant mass; other cells of the meristem gradually differentiate, forming various permanent tissues (integumentary, conducting, mechanical, basic, etc.). In higher plants, the meristem arises from the embryo promeristem, which produces apical (apical) and lateral (lateral) meristems. The apical meristems - the cones of growth of the shoot and root - are laid in the embryo very early. The formation of cotyledons and the initiation of leaf primordia on the growth cone of the shoot causes the differentiation of lateral meristems into procambium and cambium.In the process of plant growth, the meristem is partially retained in its roots, in the shoot nodes, buds, internodes of the stem, etc. The spread in width of the plates of leaf primordia is due to the marginal (marginal) meristem. Due to the fact that the property of division is potentially retained in almost all living mature tissues (excluding sieve tubes), new ones can also arise in plants, the so-called. secondary meristems, for example, phellogen, which forms cork tissue, wound meristem, which produces callus, plants, new ones can also arise, so-called. secondary meristems, for example, phellogen, which forms cork tissue, wound meristem, which produces callus, plants, new ones can also arise, so-called. secondary meristems, for example, phellogen, which forms cork tissue, wound meristem, which produces callus, etc.

Micropile - from micro … and Greek. pyle - entrance, hole, - in micropyle plants, a narrow channel in the integument of the ovule (ovule) through which the pollen tube penetrates. The cells lining the micropyle form substances that promote the growth of the pollen tube.

Mulching - from the English. mulch - loose protective layer. This is covering the soil with various materials and compositions - the so-called mulch. The following are used as mulch: humus, straw, sawdust, etc. The purpose of mulching is to reduce moisture evaporation from the ground, protect the soil from sudden temperature fluctuations during the day, prevent the formation of a soil crust, see Mulching


Nastia- from the Greek. nastos - compacted - movements (bends) of plant organs with a dorsiventral structure, in response to changes in environmental factors (light, temperature, etc.), acting in an undirected manner. Growing organs are characterized by nastia resulting from uneven stretching growth. With faster growth, the top and sides of the leaf or petal bends downward (epinasty), with the opposite ratio of growth rates - upward (hyponastia). In most cases, nasic bends are caused by a change in turgor and occur as a result of an increase and decrease in the concentration of osmotically active substances (K, Cl) in specialized cells, as a result of which water absorption and turgor pressure increase or decrease. The mechanism of nastia of organs that have stopped growing is associated with a change in turgor pressure in the cells of the joints (leaf,petal). This is how, for example, the movement of leaves oriented vertically at night, the closing and opening of flowers with the change of day and night, is carried out.

The movements of the leaves of insectivorous plants are also based on turgor nastia. A special category is made up of fast nastic movements - seismonastia arising from a light blow or concussion. Their mechanism is associated with an instantaneous evoked action potential, an increase in membrane permeability and a loss of the ability of cells of the leaf joints to retain osmotically active substances and water, as a result of which turgor drops sharply. This explains, for example, the rapid folding of leaves in mimosa and some other plants (legumes, oxalis). Phytohormones (auxins, abscisic acid, ethylene) and phytochrome play a certain role in the mechanism of infusions. Depending on the nature of the stimulus, plants are characterized by photo-, hydro-, chemo-, seismic-, nikti-, tigmo-, traumatic- and electrons. Nastic movements provide organ protection (closing flowers,stomata, drooping leaves) and capture of objects (movement of antennae, glandular hairs). Nastia is a more perfect form of movement than tropisms.


Perianth - perianthium - is a set of integumentary leaves of a flower surrounding the stamens and carpels. If the perianth consists of leaves of the same color and shape (tulip), then it is called simple. If the perianth is divided into a calyx and a corolla (gloxinia) - double.

Calyx - calyx - the outer part of the double perianth, usually green. It can be split-leaved, if the sepals that form it are free, and spinal, in which the tube and teeth are distinguished. The main function of the calyx is to protect other parts of the flower, and therefore the calyx develops very early. It is of leaf origin. So, the calyx is the sepals - taken together.

Corolla - corolla - the inner, most visible part of the double perianth, which serves to attract pollinators. The leaves that form the corolla are called petals.

Oculus (or peephole grafting ) - consists of peephole grafting (peephole - oculus) and is carried out at the time when the bark is separated. The peephole is cut off - the shield around the formed kidney is mandatory until the onset of bud opening. Otherwise, the vaccination will fail. On the rootstock, the bark is cut to the size of the oculus shield. The cut peephole is applied to the stock and carefully wound, leaving only the bud. In this case, the parts of the scion (scutellum) in contact with the stock must have live active cambium cells.

Fertilization - in the anther of a flower, the nucleus of pollen cells is divided into two nuclei: one is vegetative, the other is generative. As a result of this, two cells are formed - vegetative and generative, enclosed in a common shell. The pollen caught on the stigma of the pistil forms a pollen tube, into which its contents, consisting of these two cells, pass.

In the pollen tube, the generative cell divides into two male gametes (sperm cells). The pollen tube penetrates through the tissue of the column into the ovary through the pollen entrance to the embryonic sac of the ovary. In this case, one of the sperm of the pollen tube merges with the egg, the other with the secondary nucleus of the embryonic sac. From a fertilized egg, an embryo develops, and from a fertilized secondary nucleus of the embryonic sac - endosperm - nutritive tissue for a developing embryo.

In some plants, the embryo develops from an unfertilized egg - in a virgin way - parthenogenesis.

Suberization is a change in the primary membrane of a plant cell as a result of the deposition of suberin layers on it and their separation from the cell contents by the cellulose tertiary membrane. Corking is characteristic of cells of integumentary tissues - exoderm and cork, which protect the internal tissues of the root and stem from moisture loss and temperature fluctuations. Corking also helps heal wounds and heal scars after leaf fall.


Grasshopping is the removal of excess lateral shoots (stepchildren) that take away nutrients from the flowering parts of the plant. Non-flowering or poorly flowering side branches are removed. Grasshopping promotes more abundant flowering and larger flowers on the main shoots.

Parenchyma - from the Greek. parenchyma, lit. - poured nearby, - in plants, this is the main tissue, within which highly specialized (conductive, mechanical) tissues are differentiated. It consists of living, isodiametric (equal in all directions) cells that perform various functions. Parenchymal tissues can return to a meristematic state (i.e., regain the ability to divide), for example, during wound healing, tissue and organ regeneration, and the formation of adventitious roots and shoots. The main functions of the parenchyma are synthesis and storage of organic substances.

peloric flower
peloric flower

Peloric flower - from the Greek. pelorios - monstrous - a flower with a regular (actinomorphic) corolla, unlike other flowers of the same plant, which have irregular (zygomorphic) corollas. A peloric flower develops at the top of the inflorescence. It is possible that the formation of a peloric flower depends on the uniform action of gravity on the corolla due to its apical, and not lateral, position, as in other flowers.

It is generally accepted that an actinomorphic flower is the initial state of a trait, a zygomorphic one is a derivative. This phenomenon in orchids is developmental disorders, both inherited (mutations) and non-inherited, which lead to the development of actinomorphic flowers in plants in which they are normally zygomorphic.

Transplant - replacing old soil in a pot with a plant, usually with the selection of a larger container (pot, container, bowl).

Complete transplant - when all the old soil is removed and the roots are completely exposed, this is done when the land is completely unusable and all nutrients are lost (transplanting palms, ficuses, asparagus, etc.).

Incomplete transplant - when more or less of the earthen coma remains in the roots.

Renewal of the top layer of the earth - when part of the land is replaced by humus soil, since during irrigation, nutrients are leached from the top layer.

The transplant is usually carried out in the spring from March to May. Delicate plants are transplanted a little later. Plants blooming in spring are transplanted at the end of flowering. If you transplant a plant at the time of flowering or budding, then it will drop both flowers and buds. In the summer, after spring flowering, conifers are transplanted. Plants that were in warm rooms are transplanted later than those that were in cool ones. Bulbous plants are transplanted at the end of the dormant period. see "About soil and plant transplantation"

Transferring plants is a technique close to transplanting, with the difference that the clod of earth must remain intact, and the plant is transplanted into a larger pot. This technique is suitable for young herbaceous, fast-growing plants that cross several times during the spring-summer period. Transshipment, in contrast to full transplantation, does not slow down plant growth. In young plants, the formation of a felt-like layer of roots should not be allowed, but transshipment should be carried out when the roots have not yet filled the entire pot. Transfer also applies to plants that do not tolerate transplanting due to possible root damage.

Pericycle - from peri … and Greek. kyklos - a circle, pericambium, a layer of cells of the primary meristem in the roots and sometimes stems, surrounding the conducting cylinder and located under the epidermis. The pericycle consists of one (sometimes several) layers of parenchymal cells. All lateral roots are formed from the pericycle in the roots of the primary structure. In the roots of the secondary structure, with the help of pericycle cells, the cambium closes into a common ring and forms broad root rays, in which reserve substances are deposited, and the new formation of adventitious roots and buds occurs.

Pistil - (typical structure) consists of an ovary (lower expanded part), a column (middle part) and a stigma (upper part). During sexual reproduction, the pollen trapped on the stigma of the pistil forms a pollen tube, which grows through the column into the ovary to the ovule. With a pollen tube, two male reproductive cells (sperm) enter the embryo sac, fertilizing the egg and the secondary nucleus.

Picking - planting seedlings. Without a pick, dense seedlings are stretched out and may die. A pick is also needed to strengthen the root system. To cause the formation of a larger number of fibrous lateral roots, the end of the taproot of the seedling is pinched by 1/3 of its length. You can not pinch only thick juicy, fleshy roots, like those of agapanthus, palms, clivia, cyclamen, etc.

Pinching - pinching, consists in removing the apical bud, or the end of the leafy shoot by pinching (nails) or trimming (with scissors or a knife). In this case, the nearest lateral buds begin to develop intensively. Pinching is carried out after transplanting in the plant growth stage. The pinching delays the beginning of flowering, therefore, when the plant takes the necessary shape, the pinching is stopped.

Carpel- from carpellum, - the reproductive part of a flower that produces ovules (ovules). Carpels - one or more - make up the female part of the flower - gynoecium (a set of pistils on a flower). It is believed that the carpel is of leaf origin, but is not homologous to the vegetative leaf, but to the megasporophyll. The most primitive carpels consist of a short stalk (gynopodia) and a thin plate folded along the midvein, inside which the ovules sit between the veins. The edges of the plate are not completely closed and are covered with glandular hairs (stigma part), which protect the entrance to the carpel cavity from insects, and also perceive pollen and promote its germination with their secretions. In the process of evolution, a typical stigma is formed, localized upward, parts of the carpel and a column (stylole) that lifts the stigma above the ovary.A closed carpel or several carpels fused together are called a pistil.

Sexual hybridization - or crossing. When carrying out sexual hybridization, an important role is played by the stage analysis of the original forms, which makes it possible to develop new varieties and species not by chance, but systematically, foreseeing the result in advance. The requirement for parental couples is, first of all, health, good development, absence of diseases and pests.

The choice of flowers on the mother plant is of great importance. For example, Michurin found that when flowers are pollinated closer to the main vertical branches of the trunk, hybrids are obtained with a large deviation towards the mother plant, and when the flowers of horizontal branches located on the periphery of the crown are pollinated, hybrids are obtained with a deviation towards the paternal signs. It also became known that the shady side of the mother plant produces hybrids with inferior qualities in comparison with hybrids obtained from the flowers of the lighter side of the mother plant.

It is not recommended to fertilize a large number of flowers when crossing on one plant, because this leads to depletion of the plant and delay in seed ripening.

In artificial insemination, pollen is transferred to the stigma of the pistil by humans. At the same time, the pollen must be healthy and mature, for which it is taken from loose buds that are about to bloom. The petals are folded back with tweezers, and the best anthers are pinched off into a paper box. No filaments should remain on the anthers, because this can lead to pollen decay.

If necessary, the anthers are dried until cracking, in a shaded place, wrapped in a paper bag. You can store pollen in dry glass cups, covered with a light cloth (gauze). Pollen on the stigma of the pistil is applied at puberty of the stigma, as evidenced by the presence of a sweet and sticky syrupy liquid on it. The pollen is applied with a light touch of a brush, or simply with a clean, dry finger. In the event that the plant is capable of self-pollination, then they resort to castration - the removal of their own anthers.

Planting - placing a plant in a substrate for the further development of an already formed plant or its parts used for vegetative propagation, cuttings, bulbs, etc.

Potting soil - artificial soil of various compositions for growing plants in containers. Soil mixture for indoor plants is compiled in accordance with the requirements of a particular plant for the lightness of the soil, its acidity, friability, nutritional value. For most plants, standard soil mixtures are assumed containing humus, greenhouse, coniferous, leafy soil, peat and loosening agents - perlite, vermiculite, expanded clay in various proportions, see "About soil and plant transplantation"

Grafting is a vegetative way of plant propagation by combining parts of several plants; it is used in citrus growing. A plant that uses a stem and root system is called a stock, and a stem with leaves of a second plant grafted onto it is called a scion. The graft is a shoot of a cultivated plant and is grafted onto the stem and root system of a stock, usually uncultivated, but more resistant to external conditions and plant diseases. The root system of the stock is usually more powerful, strong, frost-resistant (in garden ones). For the grafting to succeed, a close contact of the tissues of the vascular cambium of the stock and the scion is necessary, for this it is important that the tissues of both plants are in good condition.

Grafting of whips - used for woody and herbaceous plants - the rootstock cut across is split along or crosswise. Two or four scions are inserted into the split, pointed at the end, then tied and greased with garden var.

Grafting with a bud - a dormant bud from a scion is grafted onto the stem of the stock. In this case, the bud of the scion is cut along with the underlying tissues, and then inserted into a T-shaped incision on the stem of the stock. The bud is fixed, and when it takes root, the stem of the rootstock is cut above the grafted bud, which causes the growth of the shoot from the scion bud.

Conductive tissues - textus conduc-torii - plant tissues that serve for the movement of nutrients through the plant. Water and minerals dissolved in it move from the soil along the xylem from roots to leaves, along the phloemfrom leaves to other organs (roots, buds, flowers, fruits) - substances synthesized in leaves, mainly products of photosynthesis. Conductive tissues form a continuous branched system in the body of the plant, connecting all its organs. Conductive tissues include conductive, mechanical, storage, and excretory elements. The water-conducting elements of the xylem (tracheids, vessels) rapidly differentiate, become woody, lose protoplast, and function for a long time in a dead state. Phloem sieve elements form more slowly and function as conductive tissues only in a living state, for one year. Xylem and phloem are usually located side by side, forming cords, or vascular bundles.

Prokambium - from lat. pro - before, before, instead of cambium, - part of the apical meristem. It is laid in the shoot apex, in the area of ​​formation of leaf primordia and near the distal zone of the root apex. The cells of the procambium are highly elongated, thin-walled, arranged in the form of strands connecting the leaf primordia with the rudimentary stem and forming a single procambial system. The number of strands between the stem and the leaf is constant for the species (an important taxonomic feature). At the root, the cambium looks like a column and occupies a central position. Subsequently, cambium cells differentiate into primary conductive tissue or into primary conductive tissue and cambium.


Plant tissue is a complex of cells that have the same structure and origin and perform the same function. Plant tissues are meristematic, educational, and permanent. Permanent tissues are integumentary, basic, mechanical, conductive and excretory. Tissue of cells of equal size in all directions or slightly elongated is called the main tissue or parenchyma. The main tissues include, in turn, assimilation, storage, air, etc.

  • The integumentary tissue is the skin, or epidermis, cork and crust. Nutrients are deposited in the main storage tissue. The process of photosynthesis takes place in the assimilation tissue. Mechanical tissues (collenchyme, sclerenchyma, etc.) give the plant organs strength.
  • The passing tissues include the trachea and tracheids, through which the ascending current (water and nutrients) passes, and the sieve tubes, through which the descending current (plastic substances) passes. The ascending current from the roots to the leaves goes through the vessels at a speed of about 2-4 meters per hour. Downward current through sieve tubes at a speed of about 0.7 - 1.7 m per hour.

Rhizosphere - from the Greek. rhiza root and sphaira - a ball - is a layer of soil (2-3 mm), directly adjacent to the root of the plant and is characterized by a high content of microorganisms. The composition of the microflora of the rhizosphere depends mainly on the type of soil, species and age of plants. The action of microorganisms in the rhizosphere is diverse: they convert some soil compounds difficult to assimilate by plants into easily digestible ones, synthesize biologically active substances, enter into symbiosis with plants, release toxins, participate in denitrification (the process of restoring gaseous nitrogen compounds from nitrates and nitrites), etc.


Self - seeding - young plants formed from spontaneous shedding and germination of seeds from trees and shrubs, as well as herbaceous flowering plants.

Light-loving plants are heliophytes, plants in open areas that cannot tolerate prolonged shading. They have relatively thick leaves with small cell columnar and spongy parenchyma and a large number of stomata. Leaf cells contain a significantly larger number (from 50 to 300) chloroplasts than shade-tolerant plants. Light-loving plants are characterized by a high intensity of photosynthesis. These are mainly plants of steppes, hills and semi-deserts.

Cotyledons- cotyledonis - the first leaves of plants that develop in a seed on an as yet undifferentiated embryo. In form, anatomy, structure and functions, they often differ sharply from the true leaves formed on the growth cone of the shoot. In conifers, usually, several cotyledons (from 2 to 15), in dicotyledons - 2, in monocotyledons - 1. In some dicotyledons, the embryo bears 1 cotyledon (cyclamen, etc.); and vice versa, among some monocotyledons, an embryo with 2 cotyledons (commelina, dioscorea), but this phenomenon is secondary. With aboveground germination, the cotyledons turn green and are capable of photosynthesis, and with underground germination, they serve as a storage of quotation substances (for example, in hazel, oak), in seeds with endosperm they supply quotation substances to the aerial part of the seedling. Sometimes in dicotyledons, for example, in the peperomia Peperomia, one cotyledon remains in the seed, while the other comes out of the seed and turns green.Probably, in the process of evolution, the monocotyledonous embryo evolved from the dicotyledonous as a result of the reduction of the second cotyledon. After germination, the cotyledons remain alive on the plant, sometimes for several months (ivy).

Scarification of seeds - scarifico - I scratch, I cut - mechanical breaking of the seed coat. It is used to obtain better germination and germination of seeds with a very hard seed coat (legumes, pelargonium, etc.). The seeds are passed through machines-scarifiers or treated with strong sulfuric acid and other methods. One of the homemade scarification methods is rubbing the seeds between two wooden planks with strips of fine-grained sandpaper glued to them. Also, the shell of the seed can be cut or pricked with a sharp needle, scalpel, or file, but what is very important - from the side opposite to the root of the embryo! Otherwise, the seed will die.

Dormant buds are lateral buds that are inhibited for a long time and do not sprout.

Inflorescence - inflorescentia, - shoot (or shoot system) of a plant that bears flowers. Inflorescences are common to most flowering plants. They are subdivided depending on the degree of branching. The number of flowers depends on the type of plant and can be calculated both in several units and in several tens of thousands (in some species of agaves, palms).

Shooting - premature peduncle formation, flowering and seed ripening.

Seed stratification- stratum - flooring, layer and facio - do - one of the methods of pre-sowing seed preparation to accelerate germination. The purpose of the method is to sustain seeds in conditions close to natural conditions, in which some types of trees, shrubs and other plants (fruit, some medicinal, conifers) inevitably end up. Once planted, immediately after being harvested for germination, these seeds will not sprout. they require a period of rest in humid and cool conditions, so they are comfortable with stratification. It consists in the fact that the seeds are layered with sand, sawdust, finely chopped peat, moss, or placed in several layers of gauze napkins. Then they are moistened and kept at 3 - 5 degrees and free access of air (the temperature of stratification depends on the type of plant, so for some conifers it should be around zero).At this time, the seeds ripen and come out of dormancy. The duration of stratification for different crops is not the same, for example, apple and pear seeds withstand 120 … 130 days, cedar 50 - 60 days. Important! Seeds should not dry out during stratification!

Succulents - from the Latin succulentus - juicy. This is a group of drought-resistant plants capable of accumulating moisture in their organs (stems, roots, or leaves) and storing it for a long time, thus safely surviving the dry season. All succulents are xerophytes. Read more »» about succulents.


Taxon - a group of objects related to one degree or another of common properties and characteristics and, due to this, giving grounds for assigning them to a certain taxonomic category, for example, species, genus, family.

Shade-tolerant plants - sciophytes - plants that tolerate some shade, but grow well in direct sunlight. Leaves of shade-tolerant plants with poorly differentiated columnar and spongy parenchyma; cells with a small number of chloroplasts and a relatively low rate of photosynthesis. Shade-tolerant plants include mainly mosses and lichens, some woody and herbaceous plants.

Transpiration is the evaporation of water by plants. Transpiration provides a continuous flow of water with nutrients from the soil from the roots to the leaves - it drives the aqueous solution from the soil to the plant. As a result of energy absorption, the plant overheats, and if there was no evaporation of water, then the plant could die from strong overheating.

Evaporation occurs through the stomata and, to a lesser extent, through the cuticle covering the leaf epidermis, and depends on the temperature and humidity of the air, as well as on the soil, air movement, and light intensity. Transpiration increases with an increase in temperature and an increase in illumination, and decreases with a lack of moisture in the soil. That is why rare plants tolerate hot air and bright lighting at the same time. Overheating, the plant loses its turgor and withers.

Tribe - the rank of taxon; in the hierarchy of biological taxonomy, the tribe is below the family and above the genus. Those. species of different plants are combined into genus, genus can be combined into subtribes, and subtribes into tribes, tribes into subfamilies, families into families. This classification is typical only for very large families, for example, for cacti and amaryllis. Many other families are not classified down to tribes or subtribes.

Tropisms- from the Greek. tropos - turn, direction - directed growth movements (bends) of plant organs caused by the one-sided effect of various environmental factors (light, gravity, chemicals, etc.). The phenomenon of irritability is the cornerstone of tropism. Tropism occurs in the growing parts of the plant and is usually the result of faster cell growth on one side of the stem, root, or leaf. These stretches are associated with the asymmetric distribution of plant growth hormone (auxin) in the organ. According to modern concepts, other phytohormones (for example, abscisic acid in roots) also take part in the tropism mechanism. With positive tropism, the movement is directed towards the stimulus, with negative - away from it. Organs located along the gradient of the stimulus are called orthotropic, at right angles to it - diatropic,at any other angle - plagiotropic. Due to tropism, the orientation of organs in space occurs, which ensures the most efficient use of nutritional factors and serves to protect against harmful influences (for example, stretching and tilting the plant towards the light).

Turgor is a natural tension of plant cells. A plant can only live with a water balance, i.e. when the amount of water entering the plant is not less than it is consumed. When more water is consumed (with intensive evaporation), then the cells are dehydrated. At the same time, the tension of the plant cells is weakened, this is called the loss of turgor. At the same time, the leaves and tops of the shoots droop and wither. If the plant is not watered on time, the process can become irreversible. Loss of turgor can be caused not only by a lack of watering, but also by watering and spraying with highly concentrated solutions of mineral fertilizers.

If the plant has been flooded, the roots are damaged during transplantation, the leaves on it also become lethargic, there is a loss of turgor (the roots are not able to absorb water), the petioles turn black, the leaves turn yellow, the shoots fall. As a result of the inability to absorb water and nutrients by the roots, the plant dies. Bad turgor in this case is one of the signs of root damage.

Stamens- stamen - the male generative organ of the flower. Together, the stamens on the flower form the androecium of the flower. The stamen consists of a filament and an anther. The boot consists of two halves connected by a binder. Each half of the anther contains two or one pollen nests. Pollen (microspores) develop in pollen nests. The shape and location of the stamens may vary from plant to plant. The shape of the anthers also differs (they look like two pads, a spiral, a bell, a jug, etc.) and filaments (thick, thin, in the shape of an arrow, fused). By the way, the stamens are very changeable, in the process of evolution they are easily modified. The stamens often grow together. In the simplest, simplest version, it is as if the anthers or filaments are glued by the side surfaces.But more often fusion leads to the formation of new bizarre forms. In Compositae, the stamens are fused in the anthers, in some orchids, the stamens are fused with the pistil, in other plants, for example, the family Polemoniaceae (and other representatives of the subclass of spine-petals) stamens fuse with the petals of the corolla. It remains to add that in the process of evolution, petals were formed from the stamens as a result of mutation. It is as a result of such variability that the doubleness of the flower is formed. This knowledge is widely used by breeders in the development of new varieties and hybrids.that in the process of evolution, petals were formed from the stamens as a result of mutation. It is as a result of such variability that the doubleness of the flower is formed. This knowledge is widely used by breeders in the development of new varieties and hybrids.that in the process of evolution, petals were formed from the stamens as a result of mutation. It is as a result of such variability that the doubleness of the flower is formed. This knowledge is widely used by breeders in the development of new varieties and hybrids.


Phytoncides - from the Greek. phyton - plant and lat. caedo - I kill - biologically active substances formed by plants that kill or inhibit the growth and development of pathogenic microorganisms. Phytoncides play an important role in plant immunity, and are of great importance for humans (in the fight against pathogens of various diseases). It has long been known that a huge amount of phytoncides is found in garlic and onions, as well as in almost all conifers.

Phloem - from the Greek. phloios - bark - is a plant tissue that transports photosynthetic products from leaves to places of consumption and deposition into reserves (underground organs, growth points, ripening fruits and seeds, etc.). The primary phloem, which is subdivided into protofloem and metafloem, differentiates from procambium, the secondary (bast) is a derivative of cambium. In stems, the phloem is located outside (in some plants and on the inside) of the xylem. In leaves, the phloem faces the underside of the plate; in roots with a radial conducting bundle, phloem strands alternate with xylem strands. Phloem is also involved in the deposition of reserve substances, the release of end metabolic products, and the creation of the plant's support system.

Formation - from the point of view of agricultural technology - is a technique consisting in creating a skeleton of a plant to give the plant a certain shape and place it in space for good aeration, the most complete use of solar energy and a high yield of good quality. Formation from the point of view of floriculture is a way to give a plant a stable, beautiful shape, as well as to form a certain image (for example, a bonsai style). To do this, use pruning shoots, pinching, fastening near the support, braiding with wire, etc.

Photosynthesis is the construction of organic substances from gas, water and minerals. The intensity or speed of the process of photosynthesis in a plant depends on a number of internal and external factors. The internal factors primarily include the structure of the leaf and the content of chlorophyll in it, the rate of accumulation of photosynthetic products in chloroplasts, the effect of enzymes, and the presence of low concentrations of necessary inorganic substances. External factors are the amount and quality of light falling on the leaves, the ambient temperature, the concentration of carbon dioxide and oxygen in the atmosphere near the plant.

The rate of photosynthesis increases linearly, or in direct proportion to the increase in light intensity. As the light intensity increases further, the increase in photosynthesis becomes less and less pronounced, and finally stops when the illumination reaches a certain level of 10,000 lux. A further increase in light intensity no longer affects the rate of photosynthesis. The region of stable photosynthesis rate is called the region of light saturation. If you need to increase the rate of photosynthesis in this area, you should not change the intensity of light, but some other factors. The intensity of sunlight hitting the earth's surface on a clear summer day in many places on our planet is approximately 100,000 lux. Therefore, plants, with the exception of those growing in dense forests and in the shade,incident sunlight is enough to saturate their photosynthetic activity (the energy of quanta corresponding to the extreme parts of the visible range - violet and red, differs only twice, and all photons of this range are, in principle, capable of triggering photosynthesis).

Photosynthesis proceeds in two stages - light (photochemical) and dark (metabolic). During the light stage, high-energy products are formed: the ATP molecule and the proton carrier molecules, that is, NADPH H2, are synthesized. This is followed by the dark stage: with the participation of ATP and NADPH, CO2 is reduced to glucose (C6H12O6). There are several types of photosynthesis, differing in different groups of plants, by chemical processes during the dark stage, the so-called pathways: C3-photosynthesis, C-4 photosynthesis, CAM-type of photosynthesis.

Fungicide - from the Latin "fungus" - mushroom - preparations for the destruction of pathogens of fungal and bacterial diseases that affect many indoor and garden plants. The most common fungicides in indoor floriculture are foundazol, topaz, oxyhom, hom, maxim, etc. see Fungicides


flower structure
flower structure

Flower - flos (lat.) - a shortened modified shoot, adapted for sexual reproduction. The bisexual flower of the seed plant consists of stamens and pistils, petals and sepals. The set of stamens is called androecium, pistils - gynoecium, petals - corolla, sepals - calyx.

Sepals and petals form a perianth. The outer part of it is most often green, the inner rim is colored. There are simple perianths - with uniform leaves, corolla and calyx.

Flowers can be of the correct shape - actinomorphic, and irregular - zygomorphic. The correct shape - allowing several planes of symmetry to be drawn through the flower, only one plane of symmetry can be drawn through the wrong one (for some plants (canna) not a single plane of symmetry can be drawn). Flowers are bisexual, when they have both stamens and pistils, and unisexual, if they have only stamens (male flowers) or pistils (female flowers).

Cyclic flower - from the Greek. kyklos - a circle - a flower in which all parts (stamens, petals, etc.) are arranged in circles. Probably arose in the process of evolution from an acyclic flower with a spiral arrangement of parts. Inherent in most flowering plants. Among cyclic flowers, polycyclic flowers (more than 6 circles) are usually considered more primitive, although often a large number of circles in the androceum arise again, due to the splitting of stamens. The tetracyclic flowers are the most highly organized, which are characteristic of many synergistic flowers.

The Calvin cycle, or the C3 pathway of photosynthesis, is a series of biochemical reactions carried out by plants during photosynthesis. This is a cyclic process in which CO2 is introduced and with the participation of ATP and NADP • H. The cycle consists of three stages, various sugar phosphates are formed as intermediate products, the final products are glucose, sucrose, starch, etc.

The name was given in honor of Melvin Calvin, an American biochemist who studied the assimilation of carbon dioxide by plants (using radioactive isotopes, Calvin traced the path of oxygen in photosynthesis reactions), for which he was awarded the Nobel Prize in 1961.


The calyx is the outer part of the double perianth. Most often, the green calyx, like the leaves, has a leafy nature of origin, but it can also be colored (reddish, burgundy). The calyx-forming sepals can be fused (Kalanchoe) or separate (roses). In the accrete calyx, a tube and teeth are isolated. The function of the cup is to protect the flower, or rather the bud; it is at the moment of bud formation that the already developed sepals protect the future flower from damage. The number of sepals varies greatly from flower to flower. And maybe on average there are 4-5 of them, but there can be only 2 or many. After flowering plants and setting seeds, sepals and calyx can die off, or be modified into devices that promote the spread of seeds - tenacious hooks, tufts, etc.


Epiphylls are plants that settle on the leaves (but not on the branches and trunks, like epiphytes) of other plants (in most cases, evergreens). Distributed mainly in the humid tropics and subtropics (in the temperate zone - on the leaves of conifers). Among the epiphyllums there are algae and mosses, much less often flowering plants.

Epiphytes are plants that inhabit other plants, mainly on the trunks and branches (as opposed to epiphylls, which live on the leaves) of trees, and receive nutrients from the environment (but not from the host plant, like parasites). Found in all plant classes. Epiphytes have developed adaptations for capturing water and mineral salts from the air - spongy covers on the roots, the so-called root nests (root plexus, in which dust accumulates, fallen leaves, that is, a "soil" is formed for feeding the roots), funnel leaves, in which water accumulates, absorbed by the hairs on the inner surface of the leaves, thickened cuticle, strong leaf pubescence, etc.

Ephemera are a group of annual herbaceous plants that complete a full cycle of vegetative development in a very short period. These are mainly plants of deserts and semi-deserts or steppes. They develop intensively, bloom and bear fruit during the wet period (spring or autumn), and completely die off during the summer drought.

When compiling the dictionary, botanical dictionaries were used (M.S. Gilyarov, V.K.Mesyats, etc.) and author's notes - copying of the material is prohibited!

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